Asthma
A disease of inflammation — treated by most people as a disease of wheezing
What it is
Asthma is a chronic inflammatory disease of the airways, producing variable and largely reversible narrowing: wheeze, breathlessness, chest tightness and cough, often worse at night, and typically triggered by allergens, viral infections, exercise or cold air. The defining feature is variability — it comes and goes, which is exactly what makes it so easy to under-treat.
Why it matters
Asthma is one of the few conditions where the treatment is excellent, the evidence is settled, and people die anyway. The reason is a structural trap in the disease itself: the reliever inhaler works within seconds and feels like the real medicine, while the preventer inhaler does nothing you can feel and is therefore quietly abandoned. Reviews of asthma deaths find the same pattern over and over — heavy reliever use, unfilled preventer prescriptions. Most asthma deaths are preventable, and they are not caused by a lack of effective drugs.
What BioSignal knows about treating this
What works for Asthma
BioSignal’s clinical summary, most important first.
- Inhaled corticosteroid-containing therapy — for EVERYONE with asthma, including mild asthma
- Reliever-only (short-acting beta-agonist) treatment is NO LONGER RECOMMENDED at any severity
- As-needed inhaled steroid + fast-acting bronchodilator combination — the anti-inflammatory arrives with every reliever dose
- Long-acting bronchodilators — added to, and never used without, an inhaled steroid
- Biologics for severe eosinophilic or allergic asthma — genuinely transformative
- Inhaler technique and adherence — the most under-addressed determinants of outcome anywhere in the disease
- Weight loss where obesity is present; smoking cessation
Signal Records relevant to this condition
Interventions and contributing factors — some of these records describe a cause rather than a cure. The rating shown is BioSignal’s confidence in that Signal Record, not a claim about how well it treats this condition. Open any of them for the full evidence.
- Inhaled CorticosteroidsHigh confidence
The cornerstone of asthma treatment: fewer attacks, fewer admissions, fewer deaths. Reliever-only treatment is no longer recommended at any severity. Not the steroids used in sport. In COPD the indication is narrow — exacerbators with higher eosinophils — and pneumonia risk rises.
- Vitamin DHigh confidence
Effective for deficiency and for bone health in at-risk groups. For broad disease prevention in adults who are already replete, the largest trials are null — and confidence in that null is high. Routine testing of healthy adults is not supported.
- Vitamin CHigh confidence
Does not prevent colds — one of the best-tested negatives in nutrition. Shortens them slightly, but only if you were already taking it. Megadoses are mostly excreted: absorption saturates around 200 mg/day. Genuinely useful for iron absorption, and genuinely essential — scurvy is still real.
- Omega-3 Fatty AcidsModerate confidence
Lowers triglycerides, and reduces preterm birth in pregnancy. Routine fish oil does NOT prevent cardiovascular disease, cancer or dementia in the general population. High-dose omega-3 increases atrial fibrillation risk — a real harm most bottles do not mention.
- Curcumin (Turmeric)Limited evidence
Thousands of studies, no approved drug — because curcumin is barely absorbed and a known false positive in lab assays. Modest osteoarthritis relief is its one credible claim.
New to this? Read these first
How this usually unfolds
- Recognize risk factors
- Get diagnosed
- Track key biomarkers
- Lifestyle first
- Evidence-based treatment
- Long-term monitoring
Who is at risk
- Allergy and atopy — allergic asthma is the commonest phenotype
- Family history
- Childhood eczema and food allergy (the atopic march)
- Viral respiratory infections — the commonest trigger of an attack
- Smoking and second-hand smoke — and smoking makes inhaled steroids less effective
- Air pollution and occupational exposures
- Obesity
How it's diagnosed
Asthma should be confirmed with OBJECTIVE TESTING, and frequently is not — which is a genuine problem in both directions. Spirometry showing variable airflow obstruction that reverses with a bronchodilator is the standard; peak flow variability and FeNO (exhaled nitric oxide) support it. A meaningful proportion of people carrying an asthma diagnosis do not have asthma, having been labelled on symptoms alone — and others are missed. If you have never had a breathing test, your diagnosis has not really been made.
Key biomarkers
Lifestyle
Explore this condition across BioSignal
Related Foundations
Related Signal Records
Related body systems
Frequently asked questions
What causes asthma?
At the level of the airway, chronic inflammation — which makes the airways twitchy and prone to narrowing in response to triggers that would not bother anyone else. At the level of why you have it, it is an interaction of genetic susceptibility with environment: allergy is the commonest thread, which is why asthma, eczema and hay fever cluster in the same people and the same families. What causes an individual ATTACK is different again, and the most common culprit is not dust or pollen — it is a viral respiratory infection, the ordinary cold.
Can asthma be cured?
No — and it is worth being straight about that, because false promises in this area do real damage. Asthma is a chronic disease and it does not go away, although it can change over time and childhood asthma sometimes becomes quiet in adulthood. But the honest headline is much better than 'incurable' sounds: well-controlled asthma means no symptoms, no attacks, full exercise, normal sleep and a normal life. The realistic goal is not cure. It is control so complete that you forget you have it — and the thing standing between most people and that is a preventer inhaler they are not taking.
Should I use my rescue inhaler every day?
Needing it every day is not a routine — it is an alarm. The blue reliever relaxes the muscle around the airway and does nothing at all to the inflammation underneath, so daily use means the disease is active and untreated while you are managing the symptom. This is precisely the pattern found in people who die of asthma: heavy reliever use, and a preventer sitting in a drawer. If you are using your reliever most days, please get reviewed. It is the single most important thing on this page.
Do I really need the preventer if I feel fine?
Yes — and feeling fine is the point, not the exception to it. Asthma's inflammation is present between attacks, when you have no symptoms whatsoever, quietly keeping your airways primed. The preventer treats that. It gives you nothing you can feel, which is exactly why it gets abandoned, and why abandoning it is so dangerous: you feel completely well right up until the attack. Modern guidance goes further and no longer recommends reliever-only treatment at ANY severity, including mild asthma, because people with mild asthma still die of it.
Do breathing exercises help?
Modestly, and with an important limit that is often left out. Breathing techniques can improve symptoms and quality of life for some people, and they are a reasonable addition. They do NOT reduce airway inflammation, and they are not a substitute for an inhaled steroid. The distinction matters, because the marketing around breathing methods sometimes implies you can breathe your way off your medication. You cannot, and attempting it is how people end up in hospital.
Evidence summary
Asthma is a chronic inflammatory airway disease characterised by variable, largely reversible airflow obstruction. Inhaled corticosteroid-containing therapy reduces exacerbations, hospital admissions and mortality, and major guidelines now recommend it for all severities, explicitly abandoning short-acting beta-agonist reliever-only treatment, which is associated with severe exacerbations and death. Regimens combining an inhaled corticosteroid with a fast-acting bronchodilator, used as needed, reduce severe exacerbations in mild asthma. Long-acting beta-agonists must never be used as monotherapy. Biologic therapies targeting type-2 inflammation have strong randomised evidence in severe eosinophilic and allergic asthma. Objective diagnostic testing is recommended and frequently omitted. Vitamin D supplementation shows a modest reduction in asthma exacerbations, concentrated in those who are deficient, and is not a substitute for controller therapy. Breathing exercises improve symptoms and quality of life modestly without reducing airway inflammation. Weight loss improves asthma control in obesity, and smoking both worsens asthma and reduces the effectiveness of inhaled corticosteroids.
References & sources
- GINA Global Strategy for Asthma Management and Prevention
- National Review of Asthma Deaths — findings on reliever over-reliance and preventer under-use
- SYGMA and related trials of as-needed inhaled corticosteroid-formoterol in mild asthma
Educational information — not medical advice
Is this condition page clear, accurate, and useful? Your feedback shapes what we review next.
Give feedback